Clem, normally your history is completely accurate, but this time I need to provide a few corrections.

On 2024-08-12 10:34, Clem Cole wrote:

csh et al.).   Bob later ran a serial line up the stairwells of Cory and picked up the Ingres and the first CAD machine.  Kurt Shoens, who was the primary UCB Mail author, hacked the Berknet support into his work.  One of his primary additions was removing the "delivery" part of the mail into a separate program - that he called "delivermail." 

Actually, I'm the one who separated the delivery into another program that was indeed called "delivermail". I modified /bin/mail to do actual delivery if it was invoked with -d, otherwise call delivermail. I took out the hacks for networks such as UUCP and moved them to delivermail.

Eric Alman was the system administrator of Ing70, so Eric hacked delivermail to pass email to and from the Berknet to the ARPANET.  All was good until Ernie covax showed up and was connected to the UUCP net ;-)

That part is correct. In fact, the ARPANET was the reason for delivermail in the first place. The BerkNet hacks had already been done to /bin/mail, I think by Eric Schmidt.

Eric refers to that time as "the email format of the week" and sendmail was created to allow him to more easily handle the different formats.  By then there was the DARPA 733/822 format (user@host), Berknet (host:user), UUCP (host1!host2...!hostn!user) being sources at UCB, as well as crap showing up from the IBM Educational System, CSNET and various other places trying be exchanged.

Don't forget DECnet (host::user) and things like some mercifully dead UK network that reversed the domain names, so this mailing list would be "tuhs@org.tuhs". And the compiled in configuration that delivermail used was becoming unwieldy as the world get bigger, hence a configuration file.

But the real reason for sendmail was the advent of the Internet, which used an entirely new mail protocol called SMTP. That required implementing queuing and better error reporting than returning an exit status. Bill Joy talked me into it because "you know mail better than anyone around here." I didn't expect it to turn into the cornerstone of my professional life. There are more stories there, but they are off topic.

eric